Julius Middlethun’s portrait statue of Anton Martin Swcheigaard (1882) is one of two monumental bronze sculptures situated outside the University Aula in Oslo. Accompanying it is P. A. Munch created by Stinius Fredriksen in 1931-33. The two bronze monuments are in the University of Oslo’s art collection and were both subject to an extensive conservation project in the spring of 2019. The project was led by sculpture conservator Joanna Hench and gathered a group of conservators and students for four weeks of work. My work was primarily focused on the Anton Martin Schweigaard monument.
The bronze statue has been placed outside in the city center of Oslo since the 1880s and showed severe deterioration with loss of the original casting skin and areas with open pores in the bronze surface. A long-term accumulation of black crusts, with contrasting lines of verdigris copper corrosion, had distorted the visual impression of the sculpture’s form and impaired its overall appearance. The surface was further obscured by paint spills, bird droppings and local percipitations of rust from the sculpture’s armature.
The treatment firstly consisted of aqueous cleaning, with subsequent mechanical cleansing to even out the visual contrasts and surface roughness. Essential features with severe disfigurement were chemically retouched. The treatment was concluded by heat waxing the statue with a microcrystalline petroleum wax, followed by a thorough polishing of the entire surface. The last photo shows the statue after treatment.